Effect of pre-oxidation with chlorine dioxide on the formation of trihalomethanes and haloacetic acids in a drinking water system

La reacción entre desinfectantes y materia orgánica acuática generan subproductos de desinfección (DBPs). DBPs son motivo de preocupación en el agua potable debido a que causan daños a la salud. Esta investigación busca determinar el efecto de la pre-oxidación con ClO2 en un proceso convencional a escala de laboratorio, sobre la formación de DBPs: trihalometanos (THMs) y ácidos haloacéticos (HAAs). Se realizaron ensayos con agua de un embalse que surte una planta de tratamiento convencional de agua potable, en diferentes épocas climáticas debido a su influencia sobre la naturaleza de la materia orgánica. La aplicación de 0.3 mg/L ClO2 y la dosis de coagulante óptima para remover materia orgánica, arrojó los mejores resultados, 37 μg/L de THMs y 22 μg/L de HAAs, excepto en la época seca. Se encontró que dosis mayores de ClO2 incrementaron los DPBs. Las dosis óptimas de coagulante y de ClO2 deben ser cuidadosamente definidas.The reaction between disinfectants and aquatic organic matter generate disinfection by-products (DBPs). DBPs are of concern in the drinking water because they cause damage to health. This investigation aims to determine the effect of treatment of pre-oxidation with ClO2, in a conventional process at laboratory scale, on the formation of the DBPs: trihalomethanes (THMs) and haloacetic acids (HAAs). Trials were performed with water from a reservoir that supplies a drinking water conventional treatment plant during different climatic periods due to its influence on the nature of the organic matter. Applying 0.3 mg/L ClO2 and the optimal dose of coagulant to remove organic matter, gave the best results, 37 μg/L of THMs and 22 μg/L of HAAs, except in the dry season. It was found that higher doses of ClO2 increased DPBs. The optimal doses of coagulant and of ClO2 must be carefully defined

Eccentric Keys: conceptual Foundations for Teaching Architectural Design

Thinking processes hold a spatial dimension that define the course they take. They follow a path that has different levels of complexity and linearity, their goal is to reach the horizon starting from a vertex the position of which determines, to a large extent, their nature. Hence, it is fitting to talk about keys as eccentric strategies or tools that address architectural design and its teaching from the periphery, in the same manner as when metaphors are used to describe an idea or when an explanation is given based on the geometry and scale of the design. When the adoption of a conceptual foundation is considered, what we are contemplating is the exploration of possibilities that hold essential keys, those that rise from the heart of the matter, since they are at the basis of the design itself. Given that architecture is the spatial expression of human conduct and the realm of emotional dimensions, the voids and colors that are part of it are two creative paths that are part of the same material nature.Los procesos del pensamiento contienen una dimensión espacial que define su desarrollo. Siguen una trayectoria de diferente grado de complejidad y linealidad, buscan un horizonte y parten de un vértice cuya situación determina en buena medida su naturaleza. Así, cabría hablar de claves como llaves o de herramientas excéntricas, las que abordan el proyecto y su enseñanza de forma periférica, como el utilizar metáforas para la descripción de la idea o el basar su explicación en la geometría y escala de su forma. Cuando se plantea adoptar un fundamento conceptual se está proponiendo explorar las posibilidades que tienen claves esenciales, que se generan desde la raíz, puesto que están en la misma base del proyecto. Porque la arquitectura es expresión espacial de la conducta humana y ámbito de las dimensiones emocionales, el vacío y el color que habita en él, son dos caminos de creación de una misma naturaleza matérica

Vacíos construidos, espacio representado

El espacio no es directamente visto, no es comparable al movimiento o a la luz. La mirada –la dimensión propiamente humana de la visión– se define en su intencionalidad y finalidad. La arquitectura como “pensamiento del espacio” nos hace replantear sus propios conceptos. El edificio puede ser considerado una representación del proyecto, invirtiendo así la imagen habitual del proyecto como representación del edificio. Conecta con la idea del espacio inspirada por Bachelard: un “espacio bajo el espacio”. El espacio arquitectónico es ficción teórica construida sobre los datos de la experiencia. Con la fotografía, el análisis de su representación hace posible comprenderlo en su generación proyectual a partir de los vacíos y la sintaxis visual. El vacío resulta categoría esencial en este proceso de análisis, capaz por sí misma de cualificar y significar la imagen para el observador, clave para desentrañar su experiencia. Dispuestos activamente por el creador en un determinado orden, los vacíos organizan y definen la representación del lugar y su transformación por la arquitectura. Dirigir la atención hacía los huecos y la nada, en una especie de lectura en negativo de las imágenes de arquitectura, no construye un relato complementario o retórico. Su finalidad es la elaboración de un ensayo original, definido por su naturaleza visual, articulado en un formato concreto por la unidad gráfica, la coherencia y la homogeneidad. Para la teoría y la crítica de arquitectura, un nuevo discurso con el objetivo de comunicar la reflexión acerca del hecho arquitectónico utilizando el lenguaje fotográfico. Expresión de percepción y de estudio, de sensación y de análisis, si la fotografía se propone hoy como forma crítica, depurada en su cualificación del proceso de creación, es porque se afirma su naturaleza de instrumento para deconstruir lo invisible, de explicar los vacíos. Recorridos, paréntesis y silencios adjetivan cada imagen como objeto único, emisor de señales cuya disección y traducción significará el ejercicio d

Hands on Methods for High Resolution Cryo-Electron Microscopy Structures of Heterogeneous Macromolecular Complexes

Electron microscopy of frozen hydrated samples (cryo-EM) is a powerful structural technique that allows the direct study of functional macromolecular complexes in an almost physiological environment. Protein macromolecular complexes are dynamic structures that usually hold together by an intricate network of protein-protein interactions that can be weak and transient. Moreover, a standard feature of many of these complexes is that they behave as nanomachines able to undergo functionally relevant conformational changes in one or several complex components. Among all the other main structural biology techniques, only cryo-EM has the potential of successfully dealing at the same time with both sample heterogeneity and inherent flexibility. The cryo-EM field is currently undergoing a revolution thanks to groundbreaking technical developments that have brought within our reach the possibility of solving the structure of biological complexes at atomic resolution. These technical developments have been mostly focused on new direct electron detector technology and improved sample preparation methods leading to better image quality. This fact has in turn required the development of new and better image processing algorithms to make the most of the higher quality data. The aim of this review is to provide a brief overview of some reported examples of single particle analysis strategies designed to find different conformational and compositional states within target macromolecular complex and specifically to deal with it to reach higher resolution information. Different image processing methodologies specifically aimed to symmetric or pseudo-symmetric protein complexes will also be discussed

Influence of tetrahidrocannabinol consumption in the appearance of schizophrenia and the role of nursing in patiens with dual pathology

RESUMEN: La esquizofrenia es una enfermedad mental que se caracteriza por la presencia de síntomas psicóticos y alteración de la conducta, que suele debutar por primera vez entre los 15 y los 30 años de edad. Afecta a más de de 21 millones de personas en el mundo y supone entre un 40 y un 50% de las hospitalizaciones psiquiátricas. Es una enfermedad con elevada heredabilidad genética, siendo los familiares de primer grado de una persona afectada aquellos con mayor riesgo de desarrollo de la enfermedad, aumentando éste en un 10%. Tras múltiples estudios realizados se ha evidenciado que el consumo de estupefacientes en general y de marihuana en particular supone un riesgo de aparición de experiencias delirantes 10 veces mayor. Además, los consumidores diarios de esta sustancia tienen un inicio medio de síntomas de la esquizofrenia 6 años más temprano que aquellas personas que no la consumen. Es necesario el desarrollo de un plan de cuidados individualizado y focalizado en el paciente. Los pacientes con patología dual en muchas ocasiones comparten ciertos diagnósticos de enfermería, como la gestión ineficaz de la salud o el insomnio.ABSTRACT: Schizophrenia is a mental illness characterized by the presence of psychotic symptoms and behavioral disturbances, it usually debuts for the first time between 15 and 30 years old. It affects more than 21 million people in the world and involves for between 40 and 50% of psychiatric hospitalization. It is a disease with high genetic heritability, being the first-degree relatives of an affected person those with the highest risk of developing the disease, increasing this same by 10%. After multiple studies carried out, it has been shown that the consumption of narcotic drugs in general and marijuana in particular implies a risk of the appearance of delusional experiences 10 times greater. In addition, daily users of this substance have an average onset of schizophrenia symptoms 6 years earlier than those who do not use it. It is necessary to develop an individualized care plan focused on the patient. Patients with dual pathology often share certain nursing diagnoses, such as ineffective health management or insomnia.Grado en Enfermerí

Caracterización estructural de las chaperonas TBCE y TBCB, involucradas en la Homeostasis de Tubulina Alfa

Tesis doctoral inédita. Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología Molecular. Fecha de lectura: 07-05-2013Microtubules are cytoskeletal elements made up of αβ-­‐tubulin heterodimers that provide structural support for the cell and play important roles in key cellular processes such as cell division, cell motility and intracellular transport. In contrast to other cytoskeletal components (i.e. actin), the α and β-­‐tubulin heterodimer biogenesis pathway involves not only the cytosolic chaperonin CCT for proper folding of the monomer but also a number of tubulin binding cofactors (TBCA-­‐E). Upon one or several rounds of ATPase dependent cycles of CCT activity, quasi-­‐native monomers of tubulin are released from the chaperonin. These folding intermediates subsequently interact with cofactors in a stepwise process that generates assembled competent heterodimers. Furthermore, cofactors D and E can dissociate native heterodimers and might also regulate tubulin monomers degradation. Therefore, these proteins would take an important role in the spatial and temporal regulatory pathway of microtubule dynamic instability. Previously, it has been proposed that some of these domains (i.e. Ubl domains) mediate the interaction between different cofactors and those cofactors with tubulin in a regulated manner that determines microtubule stability or dynamicity. However, no cofactor-­‐cofactor complex or cofactor-­‐substrate complex structures have been solved up to now, and the specific regions of interaction remain to be mapped. Here we present a structural analysis by transmission electron microscopy and image processing techniques of the full-­‐length TBCE protein and the ternary α-­‐tubulin:TBCE:TBCB (αEB) complex. The interpretation of the reconstructed electron density maps of TBCE and αEB by fitting the already known atomic structures of several domains of the cofactors has allowed us to elucidate the protein configuration inside the complex and thus the interaction regions that mediate complex formation and stabilization. Finally, we suggest a model that may provide insights into the molecular mechanism that drives the αβ-­‐tubulin heterodimer dissociation

Structural basis of complement membrane attack complex formation

In response to complement activation, the membrane attack complex (MAC) assembles from fluid-phase proteins to form pores in lipid bilayers. MAC directly lyses pathogens by a ‘multi-hit’ mechanism; however, sublytic MAC pores on host cells activate signalling pathways. Previous studies have described the structures of individual MAC components and subcomplexes; however, the molecular details of its assembly and mechanism of action remain unresolved. Here we report the electron cryo-microscopy structure of human MAC at subnanometre resolution. Structural analyses define the stoichiometry of the complete pore and identify a network of interaction interfaces that determine its assembly mechanism. MAC adopts a ‘split-washer’ configuration, in contrast to the predicted closed ring observed for perforin and cholesterol-dependent cytolysins. Assembly precursors partially penetrate the lipid bilayer, resulting in an irregular β-barrel pore. Our results demonstrate how differences in symmetric and asymmetric components of the MAC underpin a molecular basis for pore formation and suggest a mechanism of action that extends beyond membrane penetration